1. Field of the Invention
The present invention relates to an electrical connector assembly for electrically connecting an electronic package such as a central processing unit (CPU) with a circuit substrate such as a printed circuit board (PCB), and particularly to a land grid array connector assembly having a fastening device for securing the CPU therein.
2. Description of Related Art
FIGS. 6 and 7 show a conventional land grid array (LGA) connector assembly 6 fixed on a printed circuit board (PCB) 9. The LGA connector assembly 6 comprises a fastening device 60, and a socket 61 received in the fastening device 60. The fastening device 60 comprises a generally rectangular frame 63, and a lever 62 and a clip 64 respectively mounted to opposite ends of the frame 63. The frame 63 defines a pair of locating slots 66 at one end thereof, and a pair of guiding grooves 65 at an opposite end thereof. Each guiding groove 65 is bounded by a first wall 651 and an opposite second wall 652. The lever 62 has a pair of locating portions 623 pivotally received in the locating slots 66 of the frame 63, an offset driving portion 621 between the locating portions 623, and a handle portion 622 bent perpendicularly from one of the locating portions 623. The clip 64 has a pair of securing portions 641 movably received in the guiding grooves 65 of the frame 63, and a driving hook 644 formed at a free end thereof.
In use, the clip 64 is firstly oriented perpendicular to the frame 63, with the securing portions 641 movably disposed in the guiding grooves 65 close to the first walls 651. A central processing unit (CPU) 7 is attached on the socket 61, and a copper plate 8 which functions as a heat dissipation device is attached on the CPU 7. Then the clip 64 is rotated down to a horizontal position, with a pair of pressing arms and a pair of pressing pads of the clip 64 abutting the copper plate 8. The handle portion 622 of the lever 62 is rotated down, and the driving portion 621 of the lever 62 engages in the driving hook 644 of the clip 64. The driving portion 621 drives the driving hook 644 down until the clip 64 is in a final pressing position firmly pressing the copper plate 8 on the CPU 7. However, the handle portion 622 of the lever 62 occupies an extra: space outside the frame 63 over the PCB 9. In contemporary miniaturized electronic devices such as notebook computers, this is increasingly regarded as efficient use of the valuable “real estate” of the PCB 9, and is becoming more and more undesirable and even not feasible.
The conventional LGA connector assembly 6 inherits another disadvantage. When the driving hook 644 is unduly pressed by the driving portion 621 and thus damaged, the whole clip 64 need to be changed. This results in the increased complexity and cost in repairing the LGA connector assembly 6.
In view of the above, a new LGA connector assembly that overcomes the above-mentioned disadvantages is desired.